If you really want a fast sweeper, DD is the way to go. If you choose to hurt opponents using Feraligatr's passable bulk and access to Aqua Jet, you can use Swords Dance. But if you want Dragon Dance, Horsea, Seadra, Kingdra, Dratini, Dragonair, Dragonite, Axew, Fraxure, and Haxorus all learn Dragon Dance and can breed with Feraligatr.